After the yesterday request to contractors for the immediate repair of cracks at the A2 expressway Stryków - Konotopa, the General Directorate has achieved the first Remedial Programme submitted by the DSS company constructing the C section.
Requests, in accordance with the 15.1 closure, were forwarded to all companies constructing particular sections of the A2 expressway. Remedial programmes shall be received by 8th of March. After the approval of programmes by the GDDKiA, contractors shall immediately commence the remedial works.
The remedial programmes for cracks in the construction layers of the surface shall be submitted also by contractors at the A1 and A4 expressways, which are at the construction phase at the moment.
It can be from previously conducted researches that 90 percent of already identified cracks appeared in technological welds at working parcels that is in areas of the sub-base where section of the asphalt laid one day ends and begins the section laid on the next day. The large percentage of cracks results from mechanical cuts of the bottom layer. The remaining cracks resulted from, inter alia, other mechanical damages caused by contractors, for example during assembly of drainage facilities. This indicates culpable errors in the methodology for conducting the construction work and breaches of construction regulations.
The argument raised in the meanwhile by one of contractors concerning the use of too hard asphalts - exploited at the moment by some other contractors who find in it the possibility not to grant the warranty for the road construction - was completely overruled during the special seminar of the Road and Bridge Research Institute, already in May 2011.
The specialists, during the seminar pointed out that asphalts 100/150 and 150/200 proposed by on of the contractors to use are not suitable for incorporation into the surface - due to the fact that they cause wheel-rutting of the road. For this reason, their use was abandoned already in the 90s of the previous century. The argumentation concerning the excessive rigidity of the WMS technology provided by one of the contractors was also overthrown through indicating that the proper selection of ratio of components in the bitumen mixture is the crucial factor.
The review of the surface constructed with the WMS technology conducted during the seminar evidenced the success of the method.
In conclusion, the cracks that occurred in the A1, A2 and A4 expressways that are under construction phase, are not the norm for the use of the WMS technology (high rigidity modulus). While the correct, compatible with accepted rules, use the WMS technology, which is, according to the contract is the responsibility of the contractor, shall enabling avoiding both cracking and wheel-rutting of the surface.